n = int(input())

if (n >= 30):
  print("Yes")
else:
  print("No") n = int(input()) n int(input()) int input() input if (n >= 30):
  print("Yes")
else:
  print("No") n >= 30 n 30 print("Yes") print "Yes" print("No") print "No" n = int(input()) int(input()) n
n = int(input())

if (n >= 30):
  print("Yes")
else:
  print("No")
